What are Islands and continents apart of?

Australia. .

Australia is sometimes called the island continent. There are two continents not linked to others by land bridges: Australia and Antarctica.

Both Australia and Antarctica are regarded as island continents. They are, first and foremost, continents, but because they are both surrounded by water, they are known as island continents.

Both Australia and Antarctica are island continents. They are both continents completely surrounded by water.

Some say Australia is a continent and an island, but by geographic convention, Australia is a continent, and Greenland is an island. Also, Antarctica is a continent, and not regarded as an island...